The instant disclosure generally relates to a mirror support comprising a composite, the composite comprising a plurality of interlinked or inter-connected carbon nanotubes, and a method of making the mirror support.
Mirror supports for instruments requiring precision e.g., for large telescopes, often require a myriad of compromises. An optimal mirror support would preferably include a low areal density, a high thermal conductivity, a low coefficient of thermal expansion, high stiffness, a high strength to weight ratio, high reflectivity throughout much of the UV, IR and radio spectrum, and would be superconductive when cooled below 100° K.
However, materials having the required stiffness often have a large areal density. Materials having a low coefficient of thermal expansion often have relatively low strength to weigh ratios and/or low thermal conductivity. Accordingly, there is a need in the art for a mirror support which more closely approximates an optimal mirror support.
Individual carbon nanotubes may provide at least some of the properties of a more optimal mirror support. Numerous references are directed to carbon nanotubes and there use in a variety of applications. For example, U.S. Pat. No. 7,259,106 to Jain (Jain-106) is generally directed to a circuitry sheet comprising an electronic device layer stack containing electronic devices. Jain-106 discloses the use of a temporary substrate in which a suitable conductor material may also include graphite sheets, and conductive carbon nanotubes sheets, films and foils. Jain-106 also discloses the combination of this substrate with a stiffener.
U.S. Pat. Nos. 6,756,025; 6,756,026; 6,824,755; 6,939,525; 7,048,903; 7,052,666; 7,067,098; 7,097,820; and 7,115,864; and U.S. Patent Publication Nos. 2004-0265209 and 2005-0244326 to Colbert et al. (collectively referred to herein as Colbert) are generally directed to a single-wall carbon nanotubes purification process and more particularly to a purification process that comprises heating a single-wall carbon nanotube-containing felt under oxidizing conditions to remove the amorphous carbon deposits and other contaminating materials. The felt may be heated in an aqueous solution of an inorganic oxidant, such as nitric acid, a mixture of hydrogen peroxide and sulfuric acid, or a potassium permanganate to produce a high proportion of single-wall nanotubes that are substantially free of other material.
U.S. Pat. No. 7,264,990 to Rueckes et al. (Rueckes-990) is generally directed to nanotube films and articles, and methods of making the same. Rueckes-990 discloses conductive articles including an aggregate of nanotube segments in which the nanotube segments contact other nanotube segments to define a plurality of conductive pathways along the article. The articles may be disposed on substrates, and may form an electrical network of nanotubes within the article itself. Conductive articles may be made on a substrate by forming a nanotube fabric on the substrate, and defining a pattern within the fabric in which the pattern corresponds to the conductive article. According to Rueckes-990, nanotube fabric may be formed by growing the nanotube fabric on the substrate using a catalyst, by depositing a solution of suspended nanotubes on the substrate, by spin-coating, by dipping a substrate into a solution of carbon nanotubes, or by spraying an aerosol having nanotubes onto a surface of a substrate.
U.S. Pat. Nos. 6,683,783 (Smalley-783) and its divisional applications 6,749,827, 6,949,237, 6,979,709, 6,986,876, 7,008,604, 7041,620, 7,048,999, 7,087,207, 7,105,596, 7,108,841, and 7,205,069 (collectively referred to as Smalley) are generally directed to membranes comprising an array of single-wall carbon nanotubes wherein the membrane is nanoporous. The Smalley references disclose a membrane comprising a substantially two-dimensional array of a homogeneous population of single-walled nanotubes aggregated in substantially parallel orientation to form a monolayer extending in directions substantially perpendicular to the orientation of the individual nanotubes. Smalley discloses composite materials, defined as materials that are composed of two or more discrete constituents. According to Smalley, composites include a matrix, which serves to enclose the composite and give it its bulk form, and a structural constituent, which determines the internal structure of the component. The matrix deforms and distributes an applied stress to the structural constituent. Although composites are generally extremely strong, their strength is generally anisotropic, being much less in the direction perpendicular to the plane of the composite material than any parallel direction. Smalley also discloses that composites formed in layers or in laminate strips are prone to delamination. Smalley discloses use of carbon nanotube structural constituents to improve the properties of conventional composite materials. One such example involves composites built-up of fibrous laminates impregnated and bonded with a polymer matrix material. Graphite fiber fabric layers bonded with an epoxy system is a well-known example of such a composite. By using carbon nanotube ropes or fibers that exhibit a 3-D loopy structure added only at the epoxy/graphite interfaces, resistance to delamination of the resulting laminar composite can be substantially increased. The carbon nanotube material can be dispersed in the epoxy system before impregnation (or premixed into one of the reactive components thereof). The carbon nanotube material can also be dispersed in a liquid carrier and sprayed or otherwise applied to the laminate as each graphite fabric layer is added.
U.S. Patent Publication No. 2007/0059452 to Debe et al. (Debe-452) is generally directed to a process for extending the length of nanostructured support elements of thin film layers. The processes involve the initial formation of nanostructured support elements during a first annealing step, a coating of material deposited on the nanostructured support elements, and a second annealing step wherein the initially formed nanostructured support elements longitudinally extend. Layers having extended nanostructured support elements are also described.
EP1787955 is generally directed to an aligned single layer carbon nanotube bulk structure, which comprises an assembly of a plurality of aligned single-layer carbon nanotube and has a height of not less than 10 micrometers, and an aligned single-layer carbon nanotube bulk structure which comprises an assembly of a plurality of aligned single-layer carbon nanotubes and has been patterned in a predetermined form. This structure is produced by chemical vapor deposition (CVD) of carbon nanotubes in the presence of a metal catalyst in a reactive atmosphere with an oxidizing agent, preferably water, added thereto. An aligned single-layer carbon nanotube bulk structure, which has realized high purity and significantly large scaled length or height, its production process and apparatus, and its applied products are provided.
While numerous references are directed to carbon nanotubes and there use, composites, laminates, and other substrates comprising inter-connected carbon nanotubes and/or a web of inter-connected nanotubes and/or a web of inter-connected carbon nanotubes which are also connected chemically to an interstitial matrix have been largely ignored.
Accordingly, there is a need for a mirror support having at least some of the properties of individual carbon nanotubes.